Strategy to track failure...

[CarolinaPerler]

'Working on a large application on Windows that uses the Win32::Lanman module. On XP, 2003, and 2007, the code works as written. On Win2008R2, it doesn't. We haven't tested on a huge number of machines, so I'm not sure the OS version is relevant. Maybe? Maybe not? Anyway, in the main application the problem code looks like:

-----------------
unless (Win32::Lanman::NetLocalGroupEnum('', \@arrayOfHashes))
    {
    my $error = Win32::FormatMessage Win32::Lanman::GetLastError;
    $error = Win32::Lanman::GetLastError if ($error eq "");
    throw Error::Simple($error);
    }
-----------------

We're hoping @arrayOfHashes would contain an array of groups on the machine. It doesn't and we get an error "The specified procedure could not be found." I initially thought there was something wrong with Win32::Lanman or how we were using it. So, I wrote a little test like these:

-----------------
package getGroups;
use strict;
use Win32::Lanman;
sub getGroupsViaLanman {
  my $arrayRef = shift;
  if (Win32::Lanman::NetLocalGroupEnum('', $arrayRef)){
  print "Package Array: " . Dumper($arrayRef) . "\n";     
  return $arrayRef;
  }
  else {
    my $error = Win32::Lanman::GetLastError();
    print  "ERROR: failed to get groups via Win32::Lanman::NetLocalGro
+upsEnum  ---> " . Win32::FormatMessage Win32::Lanman::GetLastError() 
+. "\n"; 
    exit;
  }
}
1;
-----------------

and

-----------------
#!perl 
use strict;
use getGroups;
my @results;
getGroups::getGroupsViaLanman(\@results);

use Data::Dumper;
print "GROUPS: " . Dumper(@results) . "\n"; 
-----------------

That works. So, Win32::Lanman and the general approach to using it work. Ergo, we must be doing something in our larger application that is stepping on something that Win32::Lanman is using.

I copied that last chunk of code into our main application, replacing the previous version and the problem persists. So, my call to Win32::Lanman::NetLocalGroupsEnum works in my trivial test and fails when the same code (verbatim) is used in the main application.

How do I figure out what that is without resorting to a brute force exercise of reviewing code, printing voluminous debug, and .... divide and conquer? I generally live in a Linux/UNIX world. This is happening on a 64bit Windows machine. Could the 64 vs 32 bit wrinkles in windows (e.g. view of registries and such) effect this? ...'Heading off to start dissecting Win32::Lanman...